Field Reliability Estimation for Cochlear Implants

Cochlear implants are electronic devices used to provide useful hearing sensations to patients with severe to profound hearing loss. Safety and reliability are considered by patients and clinicians when selecting among the different models of cochlear implants. However, comparing reliability estimates from different manufacturers is difficult because of the lack of a standardized approach for classifying and quantifying failure data. This paper develops a classification scheme for cochlear implant failures wherein each failure report is categorized based on the failure site, cause, mode, and mechanism obtained through failure modes, mechanisms, and effects analysis. Failure parameters based on the Weibull distribution are used to quantify the following reliability metrics: B₁, B₅, B₁₀, and B₅₀ lives. The developed reporting scheme provides clear and quantitative information on failure causes and failure sites for a given implant. This method provides a consistent reporting format for communicating field reliability to regulatory units, clinicians, and patients.